In April 1936, the South African National Socialist Movement, better known as the Greyshirts, distributed posters around Cape Town, South Africa to advertize a meeting on 'Grand Parade,' a notorious meeting ground and site of political incitement. Louis Weichardt, leader of the Greyshirts, addressed the crowd from on top of a lorry, decorated with swastikas. The meeting soon degenerated into a brawl with opponents, amongst them Jews, Coloureds, communists and trade unionists. This research uses this incident of mob violence in South African history to spotlight some of the ideological conflicts and controversies that emerged at the turn of the twentieth century, and that loomed larger in local politics as the century unfolded. The background to the meeting, its descent into violent chaos, and the trial that was held in its aftermath, are used to analyze the broader socioeconomic upheavals and ideological shifts occuring within South Africa at this time. The paper thus provides a microhistorical appraisal of conflicts within Cape society during the 1930s, with a focus on the strengthening of nascent networks of leftist political radicalism on the one hand, and 'volkish' nationalism on the other. The historical analysis of this event is used to grapple with broader developments, tendencies, and dilemmas in South Africa's social history during the decades preceding the Second World War. Notes, ref. [ASC Leiden abstract]